1. Field of the Invention
The present invention relates to a mechanism for adjusting driving depth of fasteners such as nails in a fastener driving tool.
2. Description of the Prior Art
A conventional fastener driving tool includes a driver guide within which a driver is reciprocally driven for driving fasteners, a contact arm vertically movable along the driver guide and having a lower end for abutting on a work, and a control mechanism operably connected to the contact arm for controlling a driving operation of the driver. A mechanism is interlocked with the contact arm for adjusting the driving depth of fasteners into the work.
Japanese Utility Model Publication No. 60-117072 discloses an adjusting mechanism utilizing a threaded member connecting an upper part of a contact arm with a lower part thereof so as to permit change of vertical stroke of the lower part.
However, the prior art adjusting mechanism requires to rotate the threaded member for each changing operation. Further, since the adjusting mechanism is disposed along the driver guide having relatively smaller size than the body of the fastener driving tool, the operation of the threaded member is very troublesome. In addition, this mechanism requires an additional mechanism for preventing the threaded member from being loosened so as to maintain its set position. This may result in increased number of parts.